1. Field of the Invention
The invention relates to an injection head for a rocket engine combustion chamber the injection head comprising a propellant feed duct, an annular cavity for distributing the propellant and into which the feed duct opens out, and an injection plate closing a face of the distribution cavity, the injection plate having holes pierced therein for receiving injectors in order to inject the propellant into the combustion chamber of the engine. The invention relates more particularly to distributing the propellant within the injection head prior to injecting the propellant into the combustion chamber. The invention applies in particular to the field of rocket-engine combustion chambers, regardless of whether they are for providing propulsion or form part of a gas generator or of a prechamber, both for civilian and military purposes.
In an injection head of the above type, it is necessary to provide good distribution of the first propellant, which is as uniform as possible over the entire injection plate in order to ensure good mixing between the two propellants, and thus in order to obtain better combustion.
2. Description Of The Related Art
Nevertheless, in most circumstances, propellant is fed into the distribution cavity from the periphery of the cavity, which means that the injectors situated at the periphery are often favored to the detriment of centrally-located injectors. Large differences of pressure or flow rate are then observed between the outside and the center of the injection plate.
In order to remedy that problem, various solutions are conventionally implemented for achieving good propellant distribution. This function may thus be performed by having an appropriate shape for the distribution cavity or by installing continuously-varying volutes within the cavity.
Nevertheless, such solutions are expensive, not very practical, and sometimes not very effective. By way of example, providing an appropriate shape for the cavity is complex and leads to numerous mechanical and thermal constraints that require thick structures to be installed, which structures are therefore heavy: this excess structural mass naturally leads to significant extra cost in use. The use of volutes requires fabrication methods that are complex and therefore expensive.